Internal-combustion engine



E. T. KERSHAW INTERNAL COMBUSTION ENGINE I Filed Feb. 7. 19225 I INVENTOR,

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A GTTORNEYQS Patented l ter. id, liilldd.

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duplication tiled l ebruary F, 119%. derial hlo. 61?,571.

To all whom it o 4,1 concern: 1

Be it known that l, Euwiu T. Essence,- a. citizen of the United States, residing at, llenvenin the county of Denver and State Colorado, have invented certain new and useful Improvements in linternal-Gomhustion Engines; and l' do hereby declare the following to he a lull, clear, and exact the scription o:- the invention, such as will en able others skilled in the art to which it eppertains to maize and use the same.

llhis invention relates to internal combustion engines of the two-stroke-c clc type in n'l'iich a chan e of air and coin ustihle gas or other suitaole fuel is preliminarily compressed by the working stroke of each isten and introduced into the combustion space of the cylinder by the expansive force of the prccompressed charge.

In order to overcome the deficiencies due-to poor preliminiary compression in twocyclc engines has been proposed. toprovide preliminary compression chambers Within the skirted portion of a cup-shaped piston. To this lastnie'ntioned type of engine this inyention appertains and its ohject is to in ;orove the construction of engines of this type by providing means for storing a quan tity of suitable iiuel immediately adjacent the primary intalre'port so that when the, main piston is at its high point and the in take is open and the fuel is drawn, by the produced suction, immediately into the preliminary compression space in the piston, thus reducing the element oi time which would otherwise be necessary for the fuel to pass through a manifold from the carhureters and also aiding in Warming-the charge by reason of the positioning of the "fuel chamber adjacent the cylinder Wall and one haust passage.

In the accompanying drawings in which like reference characters indicate like parts hroughout the several views;

Figure 1 is a. vertical section through the cylinder and piston of an internal combustion engine embodying my invention:

Fig. 2 is a transverse section taken on the line 2-2 of Fig. l:

Fi 3 is a similar section taken on line 3- 3 of llig'. l.

In the drawings numeral 1, indicates an engine crank case of which, for convenience in illustration, only the upper part has been shown and the mechanism. contained therein such as the crank. shaft and associated mechanism being likewise omitted for convenience of illustration. The engine cylinder is indicated at 2 and is secured to the. crank case in any suitable manner as by holts 3. The cylinder shown is of the air cooled type but the invention is equally applicahle to a water cooled cylinder. The pisthn is shown at 4: and is machined on the inside to receive a stationary piston 5 which is secured to the crank casein any suitable manner as by standard 6 adjustably anchored to a cross part 7 which extends between the sides of the case. The upper end of the piston'is provided with the usual piston rings and the lower end thereof is provided with. a yachting ring 4. The piston a at its lower end above the packing ring 4e is provided with a port 4* and higher up in the opposite wall is provided with the port i the function of these ports presently appearing. 'lhecylinder is provided with a passageway or hy-pass 8, the lower end of which registers with the port i" when the piston is substantially at the bottom of its stroke, whereby a connecting passage is established, between that portion of the cylinder above the piston at and the interior of the latter this interior chamber forming a chamber in which the fuel may be preliminarily com pressed. The degree of compression desired can be varied by adjusting the stationary piston 5 with respect to its support '1' as will be readily understood. Tin exhaust port of the cylinder is indicated at 9 and is substantially opposite the upper end of the by-pass 8, it being understood that the head of the piston is provided with a battle plate for deflecting the charge of fresh iuel upwardly and away from the exhaust port 9. Surrounding the engine cylinder 2 at the region of the lay-pass 8 is u chamber 10 having an opening at 10 to the exterior and having an opening or port 10 opening into the cylinder and the opening 10 being adapted for connection to a carburetor. Vlien the piston is atthe upper end of the stroke the lower port l" thereof registers with the port 10 and fuel may then enter the chainbcr Within the piston i. The piston in moving upwardly closes the hy-pass and creates a partial vacuum in its interior chamber, and when the port 49 registers with the port 10". the fuel charge which is stored Within the storage chanibcr lO, immediately rushes into the piston interior, and on the downward stroke of the piston the charge is cornext t registers with the lower end of the ypass 8 the char e will immediately pass into the cylinder a ove the piston as will now be readily understood. The storage chamber 10 is of sufiicient capacity to hold the necessary engine charge, and by reason of the charge being stored, in close roximity to the port of entry into the pre-' iminary compression chamber within the piston 4:, not only does the charge quickly enter the preliminary compression chamber within the piston .4, but the same is also heated which is a very desirable desidcratum, especially when heavy fuels are used.

By my invention a full charge of fuel to the engine is ensured in the very short interval of time that the piston is at the top of its stroke and the speed of the engine and the power thereof are therefore maintained at a maximum, a conditibn which is not always'obtained in the ordinary type of engine because of inability of the engine to obtain the necessary fuel charge in the short interval of time allowed for that purpose.

The ellicie ncy of the present. cohstruction lies in the fact that an ample supply of fuel for the lire-compression chamber is always on storage immediately adjacent the pre-compression chamber, and ready to furnish a full supply or full charge to the precoinpression chamber whenever the port thereto is open. All loss by way of friction, and so forth, which is incident to the passage of the charge through a. long or narrow passage, is taken care of between the strokes of the piston when the charge is sucked from the carburetor into the storage chamber immediately outside of the cylinder so that when ,the pro-compression chamber is ready for its charge the full charge is immediately at hand and ready to be supplied without friction or loss of any kind, and a full charge is thus guaranteed at every stroke.

It willbe obvious that the sucking of the charge into the preliminary compression chamber will create a partial vacuumin chamber 10 which in turn will -draw a new charge into the latter chamber.

The invention. has been described with considerable particularity of detail, but it is to be understood that no limitations are intended except as may be imposed by appended claims.

What I claim is:

-1..In combination a cylinder, a skirted piston, a stationary 'hbutment telescopedby the latter, the space between the piston and abutment forming a separate initial compression space, a in pass in communication with sald space an the cylinder at a point nemesis above the piston when the latter is at the lower portion of its stroke, and a fuel storage chamber having a port opening directly into the said space when the piston is at the upper portion of its stroke.

2. The combination in an internal coinbustion engine having a separate initial com pression space between its piston and an abutment telcs'copcd by the latter, of a fuel storage chamber inunediatcly adjacent the uisite charge of fuel may pass directly into the said space upon the said port being opened for the reception of fuel, the piston controlling the opening of said port.

4. In combination, a cylin ler,-a skirted piston movable therein, an abutment orcr which the piston. is telescoped, a "fuel storage chamber contiguous the cylinder, a port inthe cylinder wall leading to said chainher, an. opening in the piston skirt adapted to register with the said port when. the piston is at the upper limit of its stroke whereby fuel may enter the piston above said :but-

. ment.

5. In combination, a cylinder, fuel storage chamber adwcent the same and having a port entering the cylinder wall, a skirted piston having in its skirt an opening adapted to r 'ister with the said chamber port when the piston is at the upper limit of its stroke, said chamber adapted to discharge gaseous fuel. into said piston when the said ports are in register, an abutment telescopcd by said piston, the latter on its downward stroke compressing the gases received therein from and a cylinder port through which the exhaust gases may 853w In testimony .w iereof he a-liixes his signature.

EDWlIl T. KERSHAW. 

